#include <iostream>

using namespace std;

void swap(int* a, int* b)
{
    int t = *a;
    *a = *b;
    *b = t;
}

int main()
{
    int a = 3;
    int b = 4;
    swap(&a, &b);
    cout << a << " " << b << endl;
    return 0;
}
